Tuning Tips

I'm stripping! My gears!

As motors become more powerful, particularly in-line drives you will have more likelyhood of stripping gears and in particular, the crown gear.

There are a number of ways that this can happen including:

  • Too much lateral movement of the motor shaft too auto align feature on the crown gear; and/or
  • The chassis is too weak for the amount of motor torque (when the motor applies torque to the rear axle the chassis may flex, causing rear axle movement).

There are a number of ways that this could be rectified and a few options are listed below (please note there are other options to fix this problem but the tips provided here bare in mind the rules of the club):

  • Shimming can be applied on the side of the rear axle between the crown gear and the axle bearing pushing the crown onto the pinion gear, thus promoting better meshing between the pinion and crown gear. This could be a good option if you do not want to modify the chassis or buy aftermarket gears.

    Shimming crown gear to force it onto the pinion gear
  • By fare the easiest fix however, would be to replace the crown gear with a good quality unit such as a slot.it. But remember to check with senior members prior to replacing any parts with aftermarket ones and make sure to keep the gear ratio the same as it were stock to be eligible to race that car.
  • If more drastic measures are required and the chassis requires serious surgery to rectify the movement/flex by reinforcing both the chassis and bearing carriers please discuss it with one of the senior members prior to carying out any work.
  • Other tips to alleviate the chances of stripping gears is to glue motors into the chassis, glue axle bearings into the bearing carriers and break in the running gear so you have nicely meshed gears.